This invention relates generally to hammer-activated, powder-actuated fastening tools and relates, more particularly, to such fastening tools which utilize a powder cartridge for providing, upon discharge of the cartridge, the driving power applied to a fastener.
The tool with which this invention is concerned includes an elongated housing within which a fastener, such as a nail or stud, is positionable, cartridge-holding means defining a bore within which a powder cartridge is operatively positionable, and an elongated firing pin for transferring the impact of a hammer to the cartridge for the purpose of discharging the cartridge. The tool also includes means for guiding the firing pin relative to the cartridge as the pin is moved from a first position at which the forward end of the firing pin is spaced from the cartridge to a second position adjacent the cartridge. By striking the rear end of the firing pin with a hammer, the firing pin moves from its first position to its second position to thereby transfer the impact of the hammer to the cartridge through the forward end of the pin. An example of a fastening tool of this class is shown and described in U.S. Pat. No. 4,025,029.
Commonly, such a tool includes no means for ensuring that the cartridge, once placed within the bore of the cartridge-holding means, is maintained in its desired position prior to discharge. Consequently, the cartridge may back out of the bore or otherwise shift in position relative thereto so as not to be properly seated within the bore when the cartridge is discharged. If the cartridge is discharged when improperly seated, the spent cartridge may jam within the bore rendering subsequent removal of the cartridge difficult. Of course, unless the spent cartridge is removed from the bore, the tool cannot be re-used.
Accordingly, it is an object of the present invention to provide a tool of the aforedescribed class having new and improved means for maintaining a powder cartridge in a properly seated position within the tool prior to discharge of the cartridge.
Another object of the present invention is to provide such a tool including means for ensuring that the cartridge is positioned in its proper position within the tool prior to discharge so that the cartridge is less likely to jam within the tool following discharge of the cartridge.
Yet another object of the present invention is to provide such a tool which is uncomplicated in construction and effective in operation.